APC UPS cable

From HwB

Cable between APC UPS and serial port of computer. Compatible with APC models 250, 400, 450, 600, 900, and 1250. APC order part #940-0020B.

Pinout

9 PIN DE-9 FEMALE to the PC.

9 PIN DE-9 MALE to the UPS.

PC		UPS
Pin	Direction	Pin	Description
5		4	Ground
8		2	Power failure
4		1	UPS Shutdown
1		5	Low Battery

Note: Add a 10kΩ restistor between pin 5 & 8 on UPS connector.

Source

• Microsoft KB 39885: Pin Connections for Cabling Between APC UPS and RS-232

Contributor

• Cosmin Dîgă
• Joakim Ögren